Summary of the previous most relevant studies showing DTI abnormalities in the grey matter in MS patients.

Abbreviations: AD – axial diffusivity, CIS – clinically isolated syndrome, Ctrl – control, FA – fractional anisotropy, GM – grey matter, MD – mean diffusivity, MS – multiple sclerosis, NAGM – normal-appearing grey matter, PPMS – primary progressive multiple sclerosis, RD – radial diffusivity, RRMS – relapsing-remitting multiple sclerosis.